Lining-fastening for electrical lamp-sockets.



E. H. FREEMAN.

LINING FASTENING FOR ELECTRICAL LAMP SOGKETS.

APILIOATION FILED JULY 22,1909.

Patented Mar. 12, 191'2.

UNITED STATES Pl/XTENT OFFQCE.

EDGAR H. FREEMAN, F TRENTON, NEW JERSEY.

LINING-FASTENING- FOR ELECTRICAL LAMP-SOCKETS.

Specification of Letters Patent.

Application filed July 22, 1909. Serial No. 508,895.

To all whom 'it may concern:

Be it known that I, EDGAR H. FREEMAN, a citizen of the United States, residing at Trenton, in the county of Mercer and State .5 of New Jersey, have invented certain new and useful Improvements in Lining-Fastenings for Electrical Lamp-Sockets, of which lthe following is a specification.

This invention relates to the subject of casings for electrical lamp sockets, and has particularly in view an improved insulatinglining fastening for the cap of the socket or cap.

Heretofore various expediente have been resorted to for the purpose of eectively securing in place what is known asthe cap lining for lamp sockets, that is, a concavoconvex or dishedwasher or lining of insulating material which registers inside of the removable cap part of a casing within Which is housed the base and operating elements of a lamp socket. Most of these expedients have involved fastening projections or eements of various kinds formed integrally or otherwise with the sheet metal cap, or with the shell part of the casing,- and coperatino with a lining which is sufficiently yieldable to be readily pressed over or snapped into engagement with such projections or elements. This particular method of fastening, that is, fastening elements or projections coperating with a yieldable or springy insulating-lining is ob. jectionable both from a structural and .manufacturers standpoint in depending upon the resiliency of the material, and in the absence of positiveness in the locker fastenin itself.

. It is or the purpose of vobviating these =0 and `other objections that the present invention is designed. j

It will therefore be understood that a special object of the present invention is to provide an improvement in cap lmlng fastenings that responds more perfectly to the requirements of the National Board of Fire Underwriters Rules which le uire that a cap of electrical lamp sockets s all be lined with insulating material that is very thin `0 and which .must be tough and tenacious,

and which lining must be so firmly secured to the shell that it will not fall out with ordinary handling of the socket. rules also re uire that the cap lining will 5 provide 'a su ciently smoothand well ini These sulated'surface for the knot to bear upon, and that there must be sufficient room in the cap to enable the ordinary wiremen to easily and quickly maite aknot in the cord and to push it intol place in the cap without crowding. These various requirements are fullyy and satisfactorily met by the present invention, while at the same time the latter pos- Patented Mar. 12, 19123,.`

sesses a very great advantage from a manufacturers standpoint in the particular yof entirely obviating careless and insecure positioning of sprung-in linings by the assemblers, which is a source of great annoyance both to the manufacturer and also to the user of the socket.

With these and many other objects in view, which will more readily appear as thc nature of the invention is better understood, the same consists in the novel construction, combination, and arrangement of parts hereinafter more fully described, illustrated, and claimed.- 4

A preferred embodiment of the invention is exemplified in the accompanying drawings, in which:

Figure 1 is an enlarged sectional View' of the casing cap of the lamp socket illustrating an insulating-lining fastened in lace according to the present invention, ig. 2 is an enlarged cross sectioal view thereof on the line 2 2 of Fig. 1. Fig. 3 is an en-l larged sectional view illustrating a method of rigidly holding or backing up the insulating-lining, while the locking spurs are forcibly upset and driven into the outer -surface of the lining.

Like references designate correspondingY 4vention shown in the drawings, the numeral l designates the cap part of a metallic casing or shell for an electrical lamp socket.v This casing cap .may be of any conventional form or design, but is usually made of sheet metal, and according to the requirements of the trade, and particularly of the fire underwriters associations, is designed to be lined upon its interior with a washer or lining 2 of 'insulating material. This washer or lining 2 is of a concave-convex or dished type, and of a size to .register snugly within the correspondinglyshaped cap.

Inasmuch as the present invention doesl not take into consideration the yielding .or springy'character of the lining, it is to be for the purpose.v

Copies of .this patent may be obtained for understood that the same may be made ot any suitable insulating `material available ,According to the present inveil'iill; t'S proposed to permanently fasten the lining 2 in place through the medium of a plu'- rality of inwardly projecting integral pointed locking spurs 3 which are forcibly punched inwardly from the bodymaterial ofthe casing, by exterior nieansy'and' driven vdirectly into the body material of the lining 2, while thelatter' is, rigidly held or backed up during the punching or upsettingoperation. Various 'mechanical appliances may be utilized for carrying out this iarticular process, but for purposes of ilfustratjion, there is shown in the' drawings theprincpal elements of an apparatus for carrying this into effect. .For instance, as shown in Fig.

3, the metal cap 1 with the lining Q thereing are set over a rigid supporting anvil 4 and are held firmly on the latter through ,the

' medium of a suitable presser or foot 5 vindicated by dotted lines in Fig. 3. 4With the parts thus arranged and held, suitably op-' erated punch points 6 are forced against and into the cap l from the exterior thereof with the result of otfsetting inwardly the pointed locking spurs Sand driving such spurs forcibly into the outer surface of the `and rigid insulating surface -for the wiring to'liearagainst, the said cap being provided in'its metal wall with a series of spaced in tegral inwardly projecting prongs penetrat ing the brous rigid body of the lining and permanently locking the same against'movehnentor displacement in any direction after the locking-in operation.

In testimony whereof-I -hereunto aiiix'my signature in the presenceof two witnesses.

EDGAR' H. FREEMAN.

.'Witnesses: i

, Bassin BATH,

MARY S. CURTIS.

five cents' each, by adclressing; oliev Commissioner of latents, WashingtonJ D. C. 

